Concurrent fabrication of and structure for capacitive terminals and ohmic terminals in a phase-change material (PCM) radio frequency (RF) switch

摘要

A radio frequency (RF) switch includes a phase-change material (PCM), a heating element underlying an active segment of the PCM and extending outward and transverse to the PCM, a capacitive RF terminal, and an ohmic RF terminal. The capacitive RF terminal can include a first trench metal liner situated on a first passive segment of the PCM, and a dielectric liner separating the first trench metal liner from a first trench metal plug. The ohmic RF terminal can include a second trench metal liner situated on a second passive segment of the PCM, and a second trench metal plug ohmically connected to the second trench metal liner. Alternatively, the capacitive RF terminal and the ohmic RF terminal can include lower metal portions and upper metal portions. A MIM capacitor can be formed by the upper metal portion of the capacitive RF terminal, an insulator, and a patterned top plate.